import { GObject } from './GObject';
import { GGroup } from './GGroup';
import { Controller } from './Controller';
import { Transition } from './Transition';
import { UIObjectFactory } from './UIObjectFactory';
import { EOverflowType, EChildrenRenderOrder } from './FieldTypes';
import { Rectangle, Margin } from '../utils/MathTypes';
import { Container } from '../display/Container';
import type { ScrollPane } from '../scroll/ScrollPane';
import type { IRenderCollector } from '../render/IRenderCollector';
import type { ByteBuffer } from '../utils/ByteBuffer';
import type { PackageItem } from '../package/PackageItem';

/**
 * GComponent
 *
 * Container class that can hold children.
 * Supports controllers, transitions, scroll, and masking.
 *
 * 容器类，可包含子对象，支持控制器、过渡动画、滚动和遮罩
 */
export class GComponent extends GObject {
    /** Opaque hit area | 不透明点击区域 */
    public opaque: boolean = true;

    protected _margin: Margin = new Margin();
    protected _trackBounds: boolean = false;
    protected _boundsChanged: boolean = false;
    protected _childrenRenderOrder: EChildrenRenderOrder = EChildrenRenderOrder.Ascent;
    protected _apexIndex: number = 0;

    protected _children: GObject[] = [];
    protected _controllers: Controller[] = [];
    protected _transitions: Transition[] = [];
    protected _scrollPane: ScrollPane | null = null;

    public _buildingDisplayList: boolean = false;
    protected _sortingChildCount: number = 0;

    // Overflow and masking | 溢出和遮罩
    protected _overflow: EOverflowType = EOverflowType.Visible;
    protected _clipRect: Rectangle | null = null;

    constructor() {
        super();
    }

    /**
     * Create display object for this component
     * 为此组件创建显示对象
     */
    protected createDisplayObject(): void {
        this._displayObject = new Container();
        this._displayObject.gOwner = this;
    }

    // Children management | 子对象管理

    /**
     * Get child count
     * 获取子对象数量
     */
    public get numChildren(): number {
        return this._children.length;
    }

    /**
     * Add a child
     * 添加子对象
     */
    public addChild(child: GObject): GObject {
        return this.addChildAt(child, this._children.length);
    }

    /**
     * Add child at specific index
     * 在指定位置添加子对象
     */
    public addChildAt(child: GObject, index: number): GObject {
        if (!child) {
            throw new Error('child is null');
        }

        const count = this._children.length;
        if (index < 0 || index > count) {
            throw new Error('Invalid child index: ' + index);
        }

        if (child._parent === this) {
            this.setChildIndex(child, index);
        } else {
            child.removeFromParent();
            child._parent = this;

            if (this._sortingChildCount > 0) {
                this._sortingChildCount++;
                index = this.getInsertPosForSortingChild(child);
            }

            this._children.splice(index, 0, child);

            this.childStateChanged(child);
            this.setBoundsChangedFlag();
        }

        return child;
    }

    /**
     * Remove a child
     * 移除子对象
     */
    public removeChild(child: GObject, bDispose: boolean = false): GObject {
        const index = this._children.indexOf(child);
        if (index !== -1) {
            return this.removeChildAt(index, bDispose);
        }
        return child;
    }

    /**
     * Remove child at index
     * 移除指定位置的子对象
     */
    public removeChildAt(index: number, bDispose: boolean = false): GObject {
        if (index < 0 || index >= this._children.length) {
            throw new Error('Invalid child index: ' + index);
        }

        const child = this._children[index];
        child._parent = null;

        if (child.sortingOrder !== 0) {
            this._sortingChildCount--;
        }

        this._children.splice(index, 1);

        if (child.internalVisible) {
            const childDisplay = child.displayObject;
            if (this._displayObject && childDisplay) {
                this._displayObject.removeChild(childDisplay);
            }
        }

        this.setBoundsChangedFlag();

        if (bDispose) {
            child.dispose();
        }

        return child;
    }

    /**
     * Remove children in range
     * 移除指定范围的子对象
     */
    public removeChildren(beginIndex: number = 0, endIndex: number = -1, bDispose: boolean = false): void {
        if (endIndex < 0 || endIndex >= this._children.length) {
            endIndex = this._children.length - 1;
        }

        for (let i = endIndex; i >= beginIndex; i--) {
            this.removeChildAt(i, bDispose);
        }
    }

    /**
     * Get child at index
     * 获取指定位置的子对象
     */
    public getChildAt(index: number): GObject {
        if (index < 0 || index >= this._children.length) {
            throw new Error('Invalid child index: ' + index);
        }
        return this._children[index];
    }

    /**
     * Get child by name
     * 通过名称获取子对象
     */
    public getChild(name: string): GObject | null {
        for (const child of this._children) {
            if (child.name === name) {
                return child;
            }
        }
        return null;
    }

    /**
     * Get visible child by name
     * 通过名称获取可见子对象
     */
    public getVisibleChild(name: string): GObject | null {
        for (const child of this._children) {
            if (child.name === name && child.internalVisible) {
                return child;
            }
        }
        return null;
    }

    /**
     * Get child by ID
     * 通过 ID 获取子对象
     */
    public getChildById(id: string): GObject | null {
        for (const child of this._children) {
            if (child.id === id) {
                return child;
            }
        }
        return null;
    }

    /**
     * Get child by path
     * 通过路径获取子对象
     */
    public getChildByPath(path: string): GObject | null {
        const arr = path.split('.');
        let obj: GObject | null = this;

        for (const part of arr) {
            if (obj instanceof GComponent) {
                obj = obj.getChild(part);
            } else {
                return null;
            }
        }

        return obj;
    }

    /**
     * Get child index
     * 获取子对象索引
     */
    public getChildIndex(child: GObject): number {
        return this._children.indexOf(child);
    }

    /**
     * Set child index
     * 设置子对象索引
     */
    public setChildIndex(child: GObject, index: number): void {
        const oldIndex = this._children.indexOf(child);
        if (oldIndex === -1) {
            throw new Error('Not a child of this container');
        }

        if (child.sortingOrder !== 0) {
            return;
        }

        const count = this._children.length;
        if (this._sortingChildCount > 0) {
            if (index > count - this._sortingChildCount - 1) {
                index = count - this._sortingChildCount - 1;
            }
        }

        this.moveChild(child, oldIndex, index);
    }

    /**
     * Set child index before another child
     * 设置子对象索引在另一个子对象之前
     */
    public setChildIndexBefore(child: GObject, beforeChild: GObject): number {
        const index = this._children.indexOf(child);
        if (index === -1) {
            throw new Error('Not a child of this container');
        }

        let beforeIndex = this._children.indexOf(beforeChild);
        if (beforeIndex === -1) {
            throw new Error('beforeChild is not a child of this container');
        }

        if (child.sortingOrder !== 0 || beforeChild.sortingOrder !== 0) {
            return index;
        }

        if (index < beforeIndex) {
            beforeIndex--;
        }

        this.moveChild(child, index, beforeIndex);
        return beforeIndex;
    }

    private moveChild(child: GObject, oldIndex: number, newIndex: number): void {
        this._children.splice(oldIndex, 1);
        this._children.splice(newIndex, 0, child);

        const childDisplay = child.displayObject;
        if (this._displayObject && childDisplay && child.internalVisible) {
            // Update display list order
            this._displayObject.setChildIndex(childDisplay, newIndex);
        }

        this.setBoundsChangedFlag();
    }

    /**
     * Swap children positions
     * 交换两个子对象位置
     */
    public swapChildren(child1: GObject, child2: GObject): void {
        const index1 = this._children.indexOf(child1);
        const index2 = this._children.indexOf(child2);
        if (index1 === -1 || index2 === -1) {
            throw new Error('Not a child of this container');
        }
        this.swapChildrenAt(index1, index2);
    }

    /**
     * Swap children at positions
     * 交换指定位置的子对象
     */
    public swapChildrenAt(index1: number, index2: number): void {
        const child1 = this._children[index1];
        const child2 = this._children[index2];

        this.setChildIndex(child1, index2);
        this.setChildIndex(child2, index1);
    }

    /**
     * Check if contains a child
     * 检查是否包含某个子对象
     */
    public isChildInView(child: GObject): boolean {
        if (this._scrollPane) {
            return this._scrollPane.isChildInView(child);
        }

        if (this._clipRect) {
            return child.x + child.width > 0 &&
                child.x < this._width &&
                child.y + child.height > 0 &&
                child.y < this._height;
        }

        return true;
    }

    /**
     * Get children in a group
     * 获取某个组内的所有子对象
     */
    public getChildrenInGroup(group: GGroup): GObject[] {
        const result: GObject[] = [];
        for (const child of this._children) {
            if (child.group === group) {
                result.push(child);
            }
        }
        return result;
    }

    private getInsertPosForSortingChild(target: GObject): number {
        const count = this._children.length;
        let i: number;
        for (i = 0; i < count; i++) {
            const child = this._children[i];
            if (child === target) continue;
            if (target.sortingOrder < child.sortingOrder) break;
        }
        return i;
    }

    // Controller management | 控制器管理

    /**
     * Get controller count
     * 获取控制器数量
     */
    public get numControllers(): number {
        return this._controllers.length;
    }

    /**
     * Get controller at index
     * 获取指定索引的控制器
     */
    public getControllerAt(index: number): Controller {
        return this._controllers[index];
    }

    /**
     * Get controller by name
     * 通过名称获取控制器
     */
    public getController(name: string): Controller | null {
        for (const c of this._controllers) {
            if (c.name === name) {
                return c;
            }
        }
        return null;
    }

    /**
     * Add controller
     * 添加控制器
     */
    public addController(controller: Controller): void {
        this._controllers.push(controller);
        controller.parent = this;
        this.applyController(controller);
    }

    /**
     * Remove controller
     * 移除控制器
     */
    public removeController(controller: Controller): void {
        const index = this._controllers.indexOf(controller);
        if (index !== -1) {
            controller.parent = null;
            this._controllers.splice(index, 1);

            for (const child of this._children) {
                child.handleControllerChanged(controller);
            }
        }
    }

    /**
     * Apply controller changes
     * 应用控制器变更
     */
    public applyController(controller: Controller): void {
        for (const child of this._children) {
            child.handleControllerChanged(controller);
        }
    }

    /**
     * Apply all controllers
     * 应用所有控制器
     */
    public applyAllControllers(): void {
        for (const c of this._controllers) {
            this.applyController(c);
        }
    }

    // Transition management | 过渡动画管理

    /**
     * Get transition at index
     * 获取指定索引的过渡动画
     */
    public getTransitionAt(index: number): Transition {
        return this._transitions[index];
    }

    /**
     * Get transition by name
     * 通过名称获取过渡动画
     */
    public getTransition(name: string): Transition | null {
        for (const t of this._transitions) {
            if (t.name === name) {
                return t;
            }
        }
        return null;
    }

    // Scroll pane | 滚动面板

    public get scrollPane(): ScrollPane | null {
        return this._scrollPane;
    }

    // Overflow | 溢出

    public get overflow(): EOverflowType {
        return this._overflow;
    }

    public set overflow(value: EOverflowType) {
        if (this._overflow !== value) {
            this._overflow = value;
            if (value === EOverflowType.Hidden) {
                this._clipRect = new Rectangle(0, 0, this._width, this._height);
            } else if (value === EOverflowType.Visible) {
                this._clipRect = null;
            }
        }
    }

    // Children render order | 子对象渲染顺序

    public get childrenRenderOrder(): EChildrenRenderOrder {
        return this._childrenRenderOrder;
    }

    public set childrenRenderOrder(value: EChildrenRenderOrder) {
        if (this._childrenRenderOrder !== value) {
            this._childrenRenderOrder = value;
            this.buildNativeDisplayList();
        }
    }

    public get apexIndex(): number {
        return this._apexIndex;
    }

    public set apexIndex(value: number) {
        if (this._apexIndex !== value) {
            this._apexIndex = value;
            if (this._childrenRenderOrder === EChildrenRenderOrder.Arch) {
                this.buildNativeDisplayList();
            }
        }
    }

    // Bounds management | 边界管理

    /**
     * Set bounds changed flag
     * 设置边界变更标记
     */
    public setBoundsChangedFlag(): void {
        if (!this._boundsChanged) {
            this._boundsChanged = true;
        }
    }

    /**
     * Ensure bounds are correct
     * 确保边界正确
     */
    public ensureBoundsCorrect(): void {
        if (this._boundsChanged) {
            this.updateBounds();
        }
    }

    protected updateBounds(): void {
        let ax = 0, ay = 0, aw = 0, ah = 0;

        for (const child of this._children) {
            const ar = child.x + child.actualWidth;
            const ab = child.y + child.actualHeight;

            if (ar > aw) aw = ar;
            if (ab > ah) ah = ab;
        }

        this.setBounds(ax, ay, aw, ah);
    }

    public setBounds(ax: number, ay: number, aw: number, ah: number): void {
        this._boundsChanged = false;
    }

    // Child state | 子对象状态

    /**
     * Notify child state changed
     * 通知子对象状态改变
     */
    public childStateChanged(child: GObject): void {
        if (this._buildingDisplayList) return;

        const childDisplay = child.displayObject;
        if (child.internalVisible) {
            if (this._displayObject && childDisplay) {
                if (childDisplay.parent !== this._displayObject) {
                    const index = this.getChildIndex(child);
                    this._displayObject.addChildAt(childDisplay, index);
                }
            }
        } else {
            if (this._displayObject && childDisplay) {
                this._displayObject.removeChild(childDisplay);
            }
        }
    }

    /**
     * Notify child sorting order changed
     * 通知子对象排序顺序改变
     */
    public childSortingOrderChanged(child: GObject, oldValue: number, newValue: number): void {
        if (newValue === 0) {
            this._sortingChildCount--;
            this.setChildIndex(child, this._children.length);
        } else {
            if (oldValue === 0) {
                this._sortingChildCount++;
            }

            const oldIndex = this._children.indexOf(child);
            const newIndex = this.getInsertPosForSortingChild(child);

            if (oldIndex < newIndex) {
                this.moveChild(child, oldIndex, newIndex - 1);
            } else {
                this.moveChild(child, oldIndex, newIndex);
            }
        }
    }

    // Display list building | 构建显示列表

    protected buildNativeDisplayList(): void {
        if (!this._displayObject) return;

        this._buildingDisplayList = true;

        const count = this._children.length;
        if (count === 0) {
            this._buildingDisplayList = false;
            return;
        }

        switch (this._childrenRenderOrder) {
            case EChildrenRenderOrder.Ascent:
                for (let i = 0; i < count; i++) {
                    const child = this._children[i];
                    const childDisplay = child.displayObject;
                    if (child.internalVisible && childDisplay) {
                        this._displayObject.addChild(childDisplay);
                    }
                }
                break;

            case EChildrenRenderOrder.Descent:
                for (let i = count - 1; i >= 0; i--) {
                    const child = this._children[i];
                    const childDisplay = child.displayObject;
                    if (child.internalVisible && childDisplay) {
                        this._displayObject.addChild(childDisplay);
                    }
                }
                break;

            case EChildrenRenderOrder.Arch:
                for (let i = 0; i < this._apexIndex; i++) {
                    const child = this._children[i];
                    const childDisplay = child.displayObject;
                    if (child.internalVisible && childDisplay) {
                        this._displayObject.addChild(childDisplay);
                    }
                }
                for (let i = count - 1; i >= this._apexIndex; i--) {
                    const child = this._children[i];
                    const childDisplay = child.displayObject;
                    if (child.internalVisible && childDisplay) {
                        this._displayObject.addChild(childDisplay);
                    }
                }
                break;
        }

        this._buildingDisplayList = false;
    }

    // Setup methods | 设置方法

    /**
     * Setup scroll pane from buffer
     * 从缓冲区设置滚动面板
     */
    protected setupScroll(_buffer: ByteBuffer): void {
        // ScrollPane setup will be implemented when needed
        // For now, create a basic scroll pane
        const { ScrollPane } = require('../scroll/ScrollPane');
        this._scrollPane = new ScrollPane(this);
    }

    /**
     * Setup overflow behavior
     * 设置溢出行为
     */
    protected setupOverflow(overflow: EOverflowType): void {
        this._overflow = overflow;
        if (overflow === EOverflowType.Hidden) {
            this._clipRect = new Rectangle(0, 0, this._width, this._height);
        }
    }

    // Construction from resource | 从资源构建

    /**
     * Construct from resource
     * 从资源构建
     */
    public constructFromResource(): void {
        this.constructFromResource2(null, 0);
    }

    /**
     * Construct from resource with object pool
     * 从资源构建（使用对象池）
     */
    public constructFromResource2(objectPool: GObject[] | null, poolIndex: number): void {
        if (!this.packageItem) {
            console.warn('[GComponent] constructFromResource2: packageItem is null');
            return;
        }

        const contentItem = this.packageItem.getBranch ? this.packageItem.getBranch() : this.packageItem;
        if (!contentItem.rawData) {
            console.warn('[GComponent] constructFromResource2: rawData is null for', contentItem.name);
            return;
        }

        const buffer = contentItem.rawData;
        buffer.seek(0, 0);

        this._underConstruct = true;

        this.sourceWidth = buffer.getInt32();
        this.sourceHeight = buffer.getInt32();
        this.initWidth = this.sourceWidth;
        this.initHeight = this.sourceHeight;

        this.setSize(this.sourceWidth, this.sourceHeight);

        if (buffer.readBool()) {
            this.minWidth = buffer.getInt32();
            this.maxWidth = buffer.getInt32();
            this.minHeight = buffer.getInt32();
            this.maxHeight = buffer.getInt32();
        }

        if (buffer.readBool()) {
            const f1 = buffer.getFloat32();
            const f2 = buffer.getFloat32();
            this.internalSetPivot(f1, f2, buffer.readBool());
        }

        if (buffer.readBool()) {
            this._margin.top = buffer.getInt32();
            this._margin.bottom = buffer.getInt32();
            this._margin.left = buffer.getInt32();
            this._margin.right = buffer.getInt32();
        }

        const overflow = buffer.readByte() as EOverflowType;
        if (overflow === EOverflowType.Scroll) {
            const savedPos = buffer.pos;
            buffer.seek(0, 7);
            this.setupScroll(buffer);
            buffer.pos = savedPos;
        } else {
            this.setupOverflow(overflow);
        }

        if (buffer.readBool()) {
            buffer.skip(8); // Skip custom data
        }

        this._buildingDisplayList = true;

        // Read controllers
        buffer.seek(0, 1);
        const controllerCount = buffer.getInt16();
        for (let i = 0; i < controllerCount; i++) {
            let nextPos = buffer.getInt16();
            nextPos += buffer.pos;

            const controller = new Controller();
            this._controllers.push(controller);
            controller.parent = this;
            controller.setup(buffer);

            buffer.pos = nextPos;
        }

        // Read children
        buffer.seek(0, 2);
        const childCount = buffer.getInt16();

        for (let i = 0; i < childCount; i++) {
            const dataLen = buffer.getInt16();
            const curPos = buffer.pos;

            let child: GObject;
            if (objectPool) {
                child = objectPool[poolIndex + i];
            } else {
                buffer.seek(curPos, 0);

                const type = buffer.readByte();
                const src = buffer.readS();
                const pkgId = buffer.readS();

                let pi: PackageItem | null = null;
                // Note: readS() returns '' for null/empty, so check for non-empty string
                if (src && contentItem.owner) {
                    const pkg = pkgId
                        ? contentItem.owner.getPackageById(pkgId)
                        : contentItem.owner;

                    pi = pkg ? pkg.getItemById(src) : null;
                } else {
                }

                if (pi) {
                    child = UIObjectFactory.newObject(pi);
                    child.constructFromResource();
                } else {
                    child = UIObjectFactory.newObject(type);
                }
            }

            child._underConstruct = true;
            child.setup_beforeAdd(buffer, curPos);
            child._parent = this;
            this._children.push(child);

            buffer.pos = curPos + dataLen;
        }

        // Setup relations for this component
        buffer.seek(0, 3);
        this.relations.setup(buffer, true);

        // Setup relations for children
        buffer.seek(0, 2);
        buffer.skip(2); // Skip child count

        for (let i = 0; i < childCount; i++) {
            let nextPos = buffer.getInt16();
            nextPos += buffer.pos;

            buffer.seek(buffer.pos, 3);
            this._children[i].relations.setup(buffer, false);

            buffer.pos = nextPos;
        }

        // Call setup_afterAdd for children
        buffer.seek(0, 2);
        buffer.skip(2); // Skip child count

        for (let i = 0; i < childCount; i++) {
            let nextPos = buffer.getInt16();
            nextPos += buffer.pos;

            const child = this._children[i];
            child.setup_afterAdd(buffer, buffer.pos);
            child._underConstruct = false;

            buffer.pos = nextPos;
        }

        // Read custom properties
        buffer.seek(0, 4);
        buffer.skip(2); // customData
        this.opaque = buffer.readBool();

        const maskId = buffer.getInt16();
        if (maskId !== -1) {
            // Mask setup - skip for now
            buffer.readBool(); // inverted mask
        }

        // Hit test - skip for now
        buffer.readS(); // hitTestId
        buffer.getInt32(); // i1
        buffer.getInt32(); // i2

        // Read transitions
        buffer.seek(0, 5);
        const transitionCount = buffer.getInt16();
        for (let i = 0; i < transitionCount; i++) {
            let nextPos = buffer.getInt16();
            nextPos += buffer.pos;

            const trans = new Transition(this);
            trans.setup(buffer);
            this._transitions.push(trans);

            buffer.pos = nextPos;
        }

        // Apply all controllers
        if (this._transitions.length > 0) {
            for (const trans of this._transitions) {
                if (trans.autoPlay) {
                    trans.play();
                }
            }
        }

        this.applyAllControllers();

        this._buildingDisplayList = false;
        this._underConstruct = false;

        this.buildNativeDisplayList();
        this.setBoundsChangedFlag();

        if (contentItem.objectType !== undefined) {
            this.constructExtension(buffer);
        }

        this.onConstruct();
    }

    /**
     * Internal set pivot
     * 内部设置轴心
     */
    protected internalSetPivot(xv: number, yv: number, bAsAnchor: boolean): void {
        this._pivotX = xv;
        this._pivotY = yv;
        this._pivotAsAnchor = bAsAnchor;
    }

    /**
     * Construct extension (override in subclasses)
     * 构建扩展（子类重写）
     */
    protected constructExtension(_buffer: ByteBuffer): void {
        // Override in subclasses
    }

    /**
     * Called after construction is complete
     * 构建完成后调用
     */
    protected onConstruct(): void {
        // Override in subclasses
    }

    // Size handling | 尺寸处理

    protected handleSizeChanged(): void {
        super.handleSizeChanged();

        if (this._clipRect) {
            this._clipRect.width = this._width;
            this._clipRect.height = this._height;
        }

        if (this._scrollPane) {
            this._scrollPane.onOwnerSizeChanged();
        }
    }

    // Disposal | 销毁

    public dispose(): void {
        for (const t of this._transitions) {
            t.dispose();
        }
        this._transitions.length = 0;

        for (const c of this._controllers) {
            c.dispose();
        }
        this._controllers.length = 0;

        if (this._scrollPane) {
            this._scrollPane.dispose();
            this._scrollPane = null;
        }

        this.removeChildren(0, -1, true);

        super.dispose();
    }

    // Render data collection | 渲染数据收集

    public collectRenderData(collector: IRenderCollector): void {
        if (!this._visible) return;

        // Update this component's display object transform
        // 更新此组件的显示对象变换
        if (this._displayObject) {
            this._displayObject.updateTransform();
        }

        if (this._clipRect) {
            collector.pushClipRect(this._clipRect);
        }

        for (const child of this._children) {
            if (child.internalVisible) {
                child.collectRenderData(collector);
            }
        }

        if (this._clipRect) {
            collector.popClipRect();
        }
    }
}